dietetics

The study or prescription of diets under special circumstances (e.g. metabolic or other illness) and for special physiological needs such as pregnancy, growth, weight reduction. See also dietitian.

The science of applying nutritional principles to the planning and preparation of foods and the regulation of the diet in relation to both health and disease.

Dietetics is the integration and application of principles derived from several disciplines—including nutrition, biochemistry, physiology, food science and composition, management, food service, and the behavioral and social sciences—to achieve and optimize human health. Dietetic professionals translate the scientific evidence regarding human nutrition and use that information to help shape the food intake or choices of the public (ADA, 2002).

Dietetic professionals work with individuals and groups of all ages to assess nutritional health and provide recommendations and therapies to assist individuals, groups, and populations in achieving a diet based on scientific evidence. The diet is generally a variety of foods but may include supplements and tube or parenteral feedings. Nutrient needs vary based on age, genetics, body composition, health status, and lifestyle. Dietetic professionals specialize in different aspects of care: They serve as translators of nutrition science to the public, as specialists in business and industry, as advocates to change food policy, as managers of food operations, as educators and researchers, and as clinicians in many different settings.

Education of Dietetic Practitioners

The majority of dietetics professionals are registered dietitians (R.D.s) and members of the American Dietetic Association. These individuals have various job titles including but not limited to dietitian, nutritionist, medical nutrition therapist, food service director, and public health or community nutritionist. The R.D. signifies that the individual has completed an academic education leading to at least a B.S. in dietetics, with coursework in nutrition, social sciences, biological sciences, and food science, along with a planned clinical experience conducted under supervision for at least six months, and has passed a national credentialing examination. The credentialing examination for the R.D. was introduced in 1969. The education and clinical experience components were first established in 1927. In 2002, about 41 percent of R.D.s had master's degrees and about 4 percent had doctorates (Bryk and Soto).

Established in the early 1980s, a two-year credential as a dietetic technician registered (D.T.R.) involves the same three-prong approach of education, experience, and examination. The D.T.R. functions clinically under the supervision of an R.D., and often manages a food-service operation. The D.T.R. has a more limited scientific education, but has similar management skills. The accreditation of entry-level dietetics programs is done by the Commission on Accreditation for Dietetic Education, and the credentialing is under the Commission on Dietetic Registration. In 2002 there were about 75,000 R.D.s or D.T.R.s in the United States.

The Evolution of Dietetic Professionals

The American Dietetic Association was founded in 1917. Its immediate goal was to assist in the feeding of World War I soldiers and to "benefit as many as possible." At that time, preventing deficiencies and providing enough food to support health were key goals. The feeding of institutionalized patients in hospitals and sanitariums quickly followed, as well as the provision of diet therapy for conditions such as diabetes mellitus and nephritis. In the 1940s, recommended dietary allowances (RDAs) were introduced, setting a standard in gauging what to feed groups; the RDAs were established to feed populations, not individuals. At the same time, the role of diet therapy was expanding. By the 1960s, understanding of the role of nutrition in the treatment of chronic diseases such as cardiovascular disease was emerging. Dietetic professionals were designing formulas for feeding patients via tubes and evaluating the composition and consistency of commercial tube-feedings that were beginning to be introduced.

In the 1970s the role of dietetic professionals expanded to include assessing the nutritional health of hospitalized patients and recommending feeding based on this assessment. Dietetic professionals began to educate the public on the use of food labeling to encourage eating properly, and to place emphasis on the use of nutrition to prevent chronic disease. Programs such as WIC (the federal Women, Infants, and Children nutrition program) expanded the dietetic practitioners' role in women's and children's health. During the 1970s roles for dietetic practitioners diversified, with dietitians working in dialysis centers, in rehabilitation, in marketing and public relations firms, and for food companies. Within the American Dietetic Association, practice groups formed to meet needs in specialty areas, for example, taking consulting roles in long-term care facilities and nutrition support roles in hospitals. During the 1980s roles continued to expand, and specialty credentials in diabetes, nutrition support, renal care, and pediatrics were introduced. The 1990s saw an expansion into outpatient care, expanding private-practice opportunities, and a movement to cross-train and become multiskilled.

Medicare part B reimbursement for nutrition counseling of nondialysis renal patients and individuals with diabetes mellitus was introduced in January 2002. It is anticipated that reimbursement would expand to cover counseling for other conditions. Private insurance coverage for medical nutrition therapy is also increasing as proper diet and lifestyle are recognized as key elements in maintaining or enhancing the health of the American public. The role of the dietetic professional continues in managing disease, has expanded in prevention, and will expand to include forecasting disease as the impact of genetics research reaches health care. As Americans eat out more and purchase more prepared foods, the role of the dietitian in dining establishments and supermarkets should expand.

The early twenty-first century is witnessing a focus on enhancing well-being and physical strength and stamina through nutrition. The dietetics profession promotes a total-diet approach to nutrition, with balance, variety, and moderation key to successful nutrition health. The newest aspects of dietetic and nutrition counseling include functional foods (that is, foods that are modified to provide a health benefit beyond the food's traditional nutrients) to enhance health, the use of dietary supplements, and the integration of alternative products such as botanicals. Dietetic practitioners assist individuals in determining if products are beneficial, whether research has been too limited to be determinative, or if the products may in fact be detrimental. Opportunities for research on the value of these products in promoting health abound. With technological advances in data collection and storage, better analysis of dietary intakes should contribute to a better understanding of the role of nutrition in health and disease.

Summary

Dietetic practitioners translate the science of nutrition into practical applications for individuals, groups, and communities. This requires a solid foundation in cultural competency, including knowledge of food composition, preparation methods and cultural values associated with particular foods, and skills in the culinary arts as well as in nutrition, science, social sciences, management, and communications. Dietetic practitioners will continue to provide nutrition therapy to individuals and groups, manage the feeding of individuals and groups, provide public education, and contribute to research about the links between food, nutrition, and health. Dietetic practitioners have a major contribution to make in the public-policy debate on issues such as obesity and its prevention and management, hunger and its prevention, and genetic modification of foods. The role of dietetic professionals will expand as nutrition becomes a major focus in addressing health issues in the nation and the world.

Bibliography

American Dietetic Association (ADA). Commission on Accreditation for Dietetics Education Accreditation Handbook. Chicago: The American Dietetic Association, 2002.

American Dietetic Association (ADA). Definition of Dietetics. January 2002.

Bryk, J., and T. Soto. "Report on the 1999 Membership Database of the American Dietetic Association." Journal of the American Dietetic Association 101(8): 947, 2001.

—Julie O'Sullivan Maillet

The science of diet and nutrition.